The acute influence of vasopressin on hemodynamic status and tissue oxygenation following the Norwood procedure

Objectives: Arginine vasopressin (AVP) is used to treat hypotension. Because AVP increases blood pressure by increasing systemic vascular resistance, it may have an adverse effect on tissue oxygenation following the Norwood procedure. Methods: Retrospective analysis of continuously captured hemodynamic data of neonates receiving AVP following the Norwood procedure. Results: We studied 64 neonates exposed to AVP within 7 days after the Norwood procedure. For the entire group, AVP significantly increased mean blood pressure (2.5 ± 6.3) and cerebral and renal oxygen extraction ratios (4.1% ± 9.6% and 2.0% ± 4.7%, respectively; P < .001 for all values). In the right ventricle to pulmonary artery shunt cohort, AVP significantly increased blood pressure, arterial oxygen saturation (1.4% ± 3.8%; P = .011), pulmonary to systemic perfusion ratio (0.2 ± 0.4; P = .017), and cerebral and renal oxygen extraction ratios (4.6% ± 8.7%; P = .010% and 4.7% ± 9.4%; P = .014, respectively). The Blalock-Taussig shunt cohort experienced a less significant vasopressor response and no change in arterial oxygen saturation, pulmonary to systemic perfusion ratio, or cerebral and renal oxygen extraction ratios. Conclusions: The right ventricle to pulmonary artery shunt cohort experienced a significant vasopressor response to AVP that was associated with a significant increase in pulmonary perfusion and decrease in cerebral and renal perfusion, whereas the Blalock-Taussig shunt cohort experienced a less significant vasopressor response and no change in pulmonary or systemic perfusion. The influence of AVP on tissue oxygenation following the Norwood procedure may have clinical implications that require further study.